Moonflowers are so named because they bloom at night. They are thought of as romantic flowers, with almost a magical quality. Many gardeners grow moonflowers along with morning glories because both plants have similar requirements. The daytime and nighttime blooms from these plants will give your garden 24 hours of flowers.
Moonflowers are vining plants that reach 15 to 20 feet in length. They tangle and climb, and must have a trellis or support. Moonflower blossoms are quite large, about six inches in diameter. They are white, creamy, or sometimes tinged with pink, which makes them seem to glow as they reflect the moonlight. In tropical regions, moonflowers are perennials. In cool northern areas they make seeds readily; they are easy to grow as annuals from seed.
The beauty of the night-blooming flowers is only part of the appeal, because the flowers are heavily fragranced as well. Plant them near the house, a window or porch where you can enjoy the scent.
Moonflowers have a very unique feature. When darkness falls, the tight buds burst open quickly. In one minute or less, the tightly rolled flower bud has completely unfurled.
Moonflower seeds can be planted outdoors when the weather has warmed in the spring, or you can start them three to four weeks early indoors and then transplant them outside. The seeds are large, about the size of raisins, and they have a very hard outer seed coat. To prepare the seeds for planting, nick each seed with a file or knife so it is easier for the baby plant to emerge, and then soak the seeds overnight in tepid water to soften the seed coat. Nick and soak the seeds whether you are planting them outdoors or indoors. Plant seeds 1/4 inch deep, and keep the soil moist. Seeds should germinate in 7 to 21 days.
Moonflowers do not like their roots to be disturbed, so peat pots or peat pellets are a good choice for starting pots. Transplant peat containers directly into the ground with a minimum of root shock.
Moonflowers prefer full sun. Space moonflower plants at least six inches apart to allow plenty of light to reach the seedlings. Mulch the plants to conserve soil moisture and keep down weeds.
Keep the soil moist, but not soggy. Moonflowers have large leaves that are easily and quickly dehydrated. The slender stems must transport water a long way to the top of the vines, so never allow the soil to completely dry out, especially during summer heat.
Moonflowers prefer average soil. If you want to fertilize moonflowers, use a soluble organic fertilizer diluted to half-strength. Remember that lots of leaves and few flowers are a sign of too much fertilizer.
Pests and Diseases
Moonflowers are not usually attacked by diseases or insects. Japanese Beetles are an exception. Control them by treating your lawn with milky spore or beneficial nematodes to kill the grub stage of the beetles.